Who is Bill Harris from Unbroken: A World War II Story of Survival, Resilience, and Redemption and what is their importance?

Bill Harris was a Marine officer and fellow prisoner of Louis Zamperini. Harris was highly intelligent and organized a system for gathering intelligence about the war from stolen newspapers and other sources which he recorded in a book that he kept secret. Harris suffered a brutal attack at the hands of a prison medical officer that seemed to affect his mental abilities. At the end of the war, Harris was selected to attend the formal signing of the papers of surrender by Japan. He returned home after the war but went back into the service to fight in Korea, where he went missing in action.